token-validator: ip, ping, ...

token-validator/challenge.go

@@ -112,6 +112,31 @@ func challengeTime(s *Student, t *givenToken, chid int) error {
 	}
 }
 
+func challengePing(s *Student, t *givenToken, chid int) error {
+	var expected []byte
+	switch s.Id % 5 {
+	case 1:
+		expected = []byte("baaaaaad")
+	case 2:
+		expected = []byte("baadfood")
+	case 3:
+		expected = []byte("baddcafe")
+	case 4:
+		expected = []byte("cafebabe")
+	default:
+		expected = []byte("deadbeef")
+	}
+
+	pkey := s.GetPKey()
+	if expectedToken, err := GenerateToken(pkey, chid, expected); err != nil {
+		return err
+	} else if ! hmac.Equal(expectedToken, t.token) {
+		return errors.New("This is not the expected token.")
+	} else {
+		return nil
+	}
+}
+
 func challengeDisk(s *Student, t *givenToken, chid int) error {
 	pkey := fmt.Sprintf("%x", s.GetPKey())
 
@@ -164,28 +189,37 @@ func init() {
 			Check: challengeTime,
 		},
 
-		/* Challenge 4 : disk */
-		Challenge{
-			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
-			Check: challengeDisk,
-		},
-
-		/* Challenge 5 : DNS TXT */
+		/* Challenge 4 : DNS TXT */
 		Challenge{
 			Accessible: []func(*Student, *http.Request) error{accessFrom(IPgwDMZ), sslOnly},
 			Check: challengeDNS,
 		},
 
-		/* Challenge 6 : time net */
+		/* Challenge 5 : time net */
 		Challenge{
 			Accessible: []func(*Student, *http.Request) error{maxProxy(1)},
 			Check: challengeTime,
 		},
+
+		/* Bonus 1 : echo request */
+		Challenge{
+			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
+			Check: challengePing,
+		},
+
+		/* Bonus 2 : disk */
+		Challenge{
+			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
+			Check: challengeDisk,
+		},
+
 	}
 
 	router.GET("/challenge", apiHandler(getChallengeList))
 	router.GET("/challenge/:chid", rawHandler(accessibleChallenge))
-	router.POST("/challenge", rawHandler(receiveToken))
+	router.POST("/challenge", rawHandler(challengeHandler(receiveToken)))
+	router.POST("/echorequest", rawHandler(definedChallengeHandler(receiveToken, 6)))
+	router.POST("/testdisk", rawHandler(definedChallengeHandler(receiveToken, 7)))
 }
 
 type givenToken struct {
@@ -219,7 +253,7 @@ func accessibleChallenge(r *http.Request, ps httprouter.Params, _ []byte) (inter
 	}
 }
 
-func receiveToken(r *http.Request, ps httprouter.Params, body []byte) (interface{}, error) {
+func receiveToken(r *http.Request, body []byte, chid int) (interface{}, error) {
 	var gt givenToken
 	if err := json.Unmarshal(body, &gt); err != nil {
 		return nil, err
@@ -231,22 +265,11 @@ func receiveToken(r *http.Request, ps httprouter.Params, body []byte) (interface
 	}
 
 	// Find challenge ID
-	var chid int
-	var err error
-	if chid, err = strconv.Atoi(string(ps.ByName("chid"))); err != nil {
-		if gt.Challenge > 0 {
-			chid = gt.Challenge
-		} else if string(ps.ByName("chid")) != "" {
-			return nil, err
-		}
-		err = nil
+	if gt.Challenge >= 1 {
+		chid = gt.Challenge
 	}
 
-	if chid == 0 {
-		chid = 4
-	}
-
-	if chid > len(challenges) {
+	if chid <= 0 || chid - 1 > len(challenges) {
 		return nil, errors.New("This challenge doesn't exist")
 	}